Weathering is the process by which rocks and other materials break down. There are two main types of weathering: physical and chemical. Physical weathering involves changes to the physical properties of rocks through processes like temperature changes, plant and animal activity, and abrasion by water or wind. Chemical weathering changes the chemical composition of rocks through reactions with substances like water, acid rain, and oxygen. Erosion is the process by which weathered materials are transported by forces like water, wind, ice, and gravity. Erosion and weathering work together over time to shape and change the Earth's surface landscape.

1. How do weathering
and erosion shape
the land?
UNIT C:
CHAPTER 5: LESSON 5:

2. Weathering
 The process in which rocks or other materials are broken down.

3. Different types of weathering:
Physical weathering
Mechanical weathering
Chemical weathering

4. Physical Weathering:
Physical weathering is when only the physical properties
change
1) Temperature changes  too hot or too cold
(Causes rocks to crack)

5. 2) Plant roots growing in rocks breaking the rocks.
Plant roots apply pressure on the rocks because
it needs space to grow

6. 3) Water freezing in cracks between rocks cause the rocks to
break apart.

7. 4) Rubbing
- running water or
- wind rubbing
dust particles
on rocks

8. 5) Animals making burrows.

9. Chemical Weathering:
Occurs when chemicals break down the rocks.
It changes the chemical composition of the rocks
1) Water dissolves
Minerals and rocks.
The agents of chemical weathering:

10. 2) Acid Rain
Formed when gases from factories combine with rain water.
It causes stones and statues to wear out and get pitted.

11. 3) Oxygen rusting Metals
Oxygen reacts with the metal component of the rock, like iron
and turns it to rust.

12. Erosion
 The process by which water, ice, wind or gravity moves
fragments of rock and soil.

13. If a particle is loosened by
weathering, but stays put, its
just weathering.
If it starts moving, its Erosion.

14. Water Erosion
 Rivers, streams, and runoff

15. Ice Erosion
 Glaciers
When part of the glacier melts and
freezes again weathered rocks get
trapped and moved with the glacier.

16. Wind Erosion

17. Mass Movements (gravity)
 Landslides and mudslides.

18. Get out a piece of paper and
identify if the following
involve weathering, erosion,
both, or neither.

19. Ready?
1.Waves are crashing on a sand
beach.
2.Water expands as it freezes in the
cracks of rocks.
3. Pebbles move down a stream with
the current.

20. 4. Acid rain causes the
decomposition of a statue in New
York.
5. A man shovels dirt to plant a tree.
6. A Glacier slowly moves down a
mountain.
7. A tree’s roots grow into the
cracks of rocks.
8. A major volcano erupts.

21. 9. A boy takes out the garbage
for his mother.
10. A shovel is left outside and
begins to rust.
Once you’ve answered these,
discuss you’re answers with the
rest of the class before you go on.

22. Let’s Discuss The Questions.
1. As the sand is moving there is
definitely erosion; there is also
abrasion from the sand gains
colliding. Both

23. 2. This is frost wedging so it’s
mechanical weathering. There
is no mention of movement.
Weathering

24. 3. There is probably some
weathering, but there is
definitely erosion. Erosion or
Both

25. 4. Acid rain on a statue is
chemical weathering. This is
mainly Weathering.

26. 5. Since the man is transporting
Earth materials, it’s Erosion.

27. 6. A glacier moving down a
mountain would have both
weathering and erosion. Both

28. 7. A tree’s roots growing into
cracks of rocks would be
weathering. Weathering

29. 8. A major volcanic eruption
would involve both weathering
and erosion. Both

30. 9. Unless the garbage has “Earth
Material” or dirt in it there is
probably no erosion or
weathering. Neither

31. 10. The rusting of a shovel is
oxidation. This is chemical
weathering. Weathering

32. The process by which materials are dropped
off at another place is called:
Deposition

34. Erosion and deposition
work together to
change the shape of
the earth’s surface.